Is Melatonin Kid-Friendly?

Did you know that the popular “sleep aid” melatonin is not a drug or medication? It’s also not a natural herb. Melatonin is actually a hormone produced in the pineal gland region of the brain. It works to help in consolidating sleep. It also has a relatively simple structure, so it can be easily synthesized, it's easy to manufacture and it’s readily available as an over-the-counter (OTC) supplement. You don’t need a prescription for melatonin. But that does not translate into “safe for anyone to use.”

Most hormone preparations require a prescription. So maybe its OTC standing explains why the average consumer thinks that melatonin is pretty innocuous. It’s also important to note that melatonin is naturally found in some foods like barley, olives, and even walnuts. It is therefore categorized as a nutritional supplement.

The first mistake that consumers make when it comes to this hormone is to think that because it’s involved in regulating sleep, taking more melatonin would help to stimulate sleep. The truth is that the role of melatonin is not as a sleep inducer, but rather it helps to regulate the wake-sleep schedule. Timing is far more important when it comes to using this supplement as you want to take it when levels of melatonin in the body should naturally be rising.

For that reason, melatonin is far more useful in regulating sleep schedules especially when it comes to jet lag or shift work. In fact, a 2002 Cochrane review that analyzed 10 randomized trials found melatonin quite effective, when timed properly, for helping to minimize jet lag. Current recommendations suggest taking melatonin for several days (afternoon or early evening timing) before arriving at a destination that involves crossing a couple to several time zones, and then taking a dose close to the new bedtime on the day of arrival.

Because melatonin is so widely available as an OTC, it’s not surprising that parents might think that their otherwise healthy but “sleep-challenged” kids might benefit from melatonin.

Studies done by Judith Owens, M.D., M.P.H. director of the Center for Pediatric Sleep Disorders at Boston Children Hospital, have raised concern about the use of melatonin in the pediatric population, and especially about long-term potential adverse effects. Concerns have arisen regarding its impact on developing reproductive, cardiovascular, immune, and metabolic systems in growing children.

In her clinical experience, Dr. Owens suggests that rarely does a family come to the clinic for help with a child who is suffering with insomnia who has not already tried melatonin. Most parents feel secure using it because it is considered a “nutritional supplement.” While short-term use of the hormone is deemed to be relatively safe, long-term use has been associated with side effects including headaches, dizziness, and daytime grogginess.

It’s not clear if those symptoms are due to changes in the internal body clock resulting from taking melatonin supplements at the wrong time, or whether the symptoms are due to the cumulative presence of the synthesized melatonin. Those are two important distinctions, and they raise concern about the very nature of this substance, looking at two very different problems.

Melatonin is a derivative of the amino acid tryptophan, one of the nine essential amino acids needed by proteins in the body. Further modifications of this compound can result in producing other hormones, including thyroid hormones, and another hormone called hydroxytryptamine, which you may know by the name serotonin, an important neurotransmitter in the brain. Serotonin has profound effects on many different functions of the brain, including mood. Mood changes are therefore a real possibility in individuals who take melatonin, especially in excess of recommended doses.

When it comes to usage in children, the effects of melatonin are more unpredictable. Kids are typically sound sleepers once they get to bed, and they should not need any sleep aides. Unlike adults who have problems maintaining sleep, when children struggle, it typically involves getting on the appropriate sleep schedule. This tends to be more of a behavioral issue, not a hormonal imbalance. To be clear, melatonin addresses a hormonal imbalance. The net effects of poor sleep are also different in children, when compared to adults. They are usually not sleepy but rather exhibit quite the opposite behaviors. Sleep-deprived children are more likely to become hyperactive and have behavioral problems.

It’s also important to discuss the quality and “real quantity” of melatonin contained in the over-the-counter commercially available products. A recent study in the Journal of Clinical Sleep Medicine found that 71 percent of melatonin samples were more than 10 percent “off the stated dose,” with a range of -83 percent to +478 percent (!) of the actual labeled content.

Eli Hendel, M.D., is a board-certified internist/pulmonary specialist with board certification in Sleep Medicine. An Assistant Clinical Professor of Medicine at Keck-University of Southern California School of Medicine, and Qualified Medical Examiner for the State of California Department of Industrial Relations, his areas include asthma, COPD, sleep disorders, obstructive sleep apnea, and occupational lung diseases. Favorite hobby? Playing jazz music.